Everything You Need to Know About Coal Tar Asphalt Sealer

When it comes to maintaining asphalt, sealcoating is an important step. It protects the surface, makes it last longer, and improves the overall appearance. But not all sealers are the same. One of the most controversial sealers out there is coal tar asphalt sealer. While it’s been used for many years, coal tar sealers are raising concerns about health and environmental safety.

In this article, we’ll dive into what coal tar asphalt sealer is, why it’s being banned in some places, the risks associated with its use, and why we prefer using asphalt emulsion instead—a safer, cleaner alternative.

What is Coal Tar Asphalt Sealer?

Coal tar asphalt sealer is a popular type of sealant used to protect and prolong the life of asphalt surfaces like driveways, parking lots, and roads. It forms a protective layer that shields the surface from water, chemicals, and UV damage. It’s been used for decades because it’s effective and long-lasting.

However, the main ingredient in coal tar sealers is coal tar pitch, which is a byproduct of the steel industry. This pitch is packed with a class of chemicals called Polycyclic Aromatic Hydrocarbons (PAHs), which are known to be harmful.

The Growing Concern About Coal Tar Sealers

Over the years, there’s been a growing concern about the health and environmental impacts of coal tar sealers. These concerns have led many states and local governments to ban or restrict their use.

Why? The main reason is that coal tar sealers contain high concentrations of PAHs. PAHs are toxic contaminants that don’t break down easily in the environment. They are linked to harmful health effects in humans and can also damage the environment.

Why Are States Banning Coal Tar Sealers?

Several states, counties, and cities across the U.S. are starting to take action by banning or limiting the use of coal tar sealers. Places like Minnesota, Washington, Texas, New York, and Washington D.C. have already implemented bans.

Why are they taking this step?

Coal tar sealers release PAHs into the environment. These chemicals can wash off asphalt surfaces during rainstorms and end up in rivers, lakes, and streams. They don’t break down easily, so they accumulate in the soil and water, where they can harm wildlife and ecosystems.

But the environmental impact isn’t the only concern. The presence of PAHs also poses a threat to human health.

Health Risks of Coal Tar Sealers

One of the biggest concerns about coal tar sealers is the health risk they pose to people who come into contact with them.

PAHs are classified as probable human carcinogens. This means that exposure to these chemicals is linked to an increased risk of developing cancer. The U.S. Environmental Protection Agency (EPA) has found that several types of PAHs can potentially cause lung, skin, and bladder cancer. Children, who are more likely to play on paved surfaces, are at a particularly high risk of exposure.

PAHs are also linked to other health issues. Studies have shown that long-term exposure to PAHs can lead to respiratory problems, skin irritation, and developmental issues in children.

The problem with coal tar sealers is that these harmful chemicals are released into the environment during and after application. People who work with coal tar sealers are exposed to high levels of PAHs during the installation process. But even after the sealant dries, PAHs can continue to be released into the air and the environment for months, if not years.

What Are PAHs?

Let’s take a closer look at Polycyclic Aromatic Hydrocarbons (PAHs). These chemicals are a class of toxic contaminants that are produced when organic substances—like coal or wood—are burned.

PAHs are made up of several connected carbon rings, which makes them very stable and difficult to break down. Once they’re in the environment, they can linger for a long time.

In nature, PAHs can come from sources like forest fires or volcanic eruptions, but human activity has greatly increased their presence in the environment. Industries like oil refining, burning coal, and the use of coal tar sealers have made PAHs much more common in our air, soil, and water.

How Do PAHs Impact the Environment?

PAHs don’t just pose a risk to human health; they also have a significant impact on the environment. Because they don’t break down easily, PAHs can accumulate in the soil and water, where they can harm plants, animals, and aquatic life.

When coal tar sealer is applied to asphalt, rainwater can wash PAHs off the surface, and they eventually make their way into storm drains, streams, rivers, and lakes. Over time, the concentration of PAHs builds up, making it difficult for aquatic ecosystems to thrive.

Fish and other wildlife can absorb PAHs, leading to long-term health problems, reproductive issues, and even death. These chemicals can also affect the microorganisms in the soil, which are important for maintaining healthy ecosystems.

Because of these risks, many environmental organizations and scientists are pushing for a complete ban on coal tar sealers to protect our natural resources.

Alternatives to Coal Tar Sealer: Asphalt Emulsion

Given the environmental and health risks associated with coal tar sealers, it’s no surprise that people are looking for safer alternatives. One of the best alternatives is asphalt emulsion.

Asphalt emulsion is a water-based product that doesn’t contain the high levels of PAHs found in coal tar. It’s made from a mixture of asphalt, water, and an emulsifying agent, which helps the asphalt spread and adhere to the surface.

Why We Use Asphalt Emulsion

At our company, we’re committed to providing a product that’s both effective and safe. That’s why we use asphalt emulsion for our sealcoating projects instead of coal tar. Here’s why we believe asphalt emulsion is the better choice:

1. Safer for Your Health

Asphalt emulsion is much safer for you, your family, and the environment because it contains significantly lower levels of PAHs. You won’t have to worry about breathing in harmful fumes during or after the application, and there’s no long-term risk of exposure to toxic chemicals.

2. Better for the Environment

Because asphalt emulsion is water-based, it doesn’t pose the same threat to our waterways and wildlife as coal tar sealers do. It doesn’t wash off into the environment the same way coal tar does, making it a greener choice for sealcoating.

3. Effective Protection

Just because asphalt emulsion is safer doesn’t mean it’s less effective. It still provides excellent protection for your asphalt surfaces, helping to prevent cracks, water damage, and wear from traffic. Asphalt emulsion is just as durable as coal tar and can extend the life of your driveway or parking lot for years.

4. Cost-Effective

While some people think that switching to a safer product might be more expensive, asphalt emulsion is actually cost-effective. It’s affordable to apply, and because it’s easier to work with, labor costs are often lower as well.

How Can You Tell If You Have Coal Tar Sealer?

If you’re not sure what type of sealer was used on your driveway or parking lot, there are a few ways to tell:

1. Check the Label: If you still have the container, look for words like “coal tar” or “refined tar.” These are red flags that you have a coal tar sealer.
2. Color and Smell: Coal tar sealers tend to be darker and have a strong chemical smell, even after they’ve dried.
3. Ask a Professional: If you’re still not sure, a professional asphalt contractor can help you identify the type of sealer used.

Make the Switch to a Safer, Cleaner Option

If you’re concerned about the potential risks of coal tar sealers, it might be time to make the switch to asphalt emulsion. Not only will you be choosing a safer, cleaner product, but you’ll also be doing your part to protect the environment.

Final Thoughts

Coal tar asphalt sealer may have been a popular choice in the past, but the risks it poses to human health and the environment make it a poor option today. With many states moving toward banning coal tar sealers, it’s clear that safer alternatives like asphalt emulsion are the way to go.

At our company, we’re proud to use asphalt emulsion for all our sealcoating projects. It’s safer, environmentally friendly, and just as effective. If you’re thinking about sealcoating your driveway or parking lot, we’re here to help.

Call us today for a free quote or just a friendly opinion. We’ll make sure your asphalt is protected without compromising your health or the environment.